MAPT and Alzheimer disease: Pathologically, AD is marked by the buildup of extracellular senile plaques mainly containing the polymerized 42 kDa amyloid-β peptide (Aβ42) and of intracellular neuronal fibrillar tangles (NTFs) resulting from the polymerization of the hyperphosphorylated tau (p-tau) protein, as well as by reactive gliosis, including microgliosis [10,11].